1. Field of the Invention
The present invention relates to an image forming apparatus that is capable of communicating with an external apparatus via a network, and a control method thereof.
2. Description of the Related Art
In recent years, a technique of cloud computing has been spreading that does not execute an application with a user's server but uses software in the form of a service provided on the internet.
The cloud computing features a service provision for a user's request without the user knowing where a program is actually executed. In a cloud computing environment, the user can advantageously reduce an initial investment for installing a server or purchasing an application.
This cloud computing environment is considered to be applied to a printer or a multifunction peripheral (MFP) capable of copying, printing, scanning, and faxing. In this case, the printer or the MFP supports a basic function, while the “cloud” on the network performs processing of an additional function, to establish a service environment for providing a low-cost MFP body or printer body, and also a high-performance added value.
As an example of a combination between the printer and the cloud, Japanese Patent Application Laid-Open No. 2003-288336 discusses a technique in which the cloud processes a function (e.g., an aggregate copy function that needs a great memory capacity, such as N-in-1) which an inexpensive printer does not deal with, and the printer performs printing. With this technique, since a printer side does not need extension but the cloud performs the processing, the printer can be reduced in its cost.
In addition, functions prospective using the cloud include Page Description Language (PDL) processing, synthetic printing by adding a bar code/copy-forgery-inhibited pattern, optical character recognition (OCR), and voice conversion.
On the other hand, reducing a consumption of electric power is an essential theme for the MFP, which can be achieved by positively reducing electric power while the MFP is not in use.
Further, generally, a cloud server is set up prior to an installation of a firewall. More specifically, a local area networks (LAN) to which the MFP is to be connected may have been provided with the firewall. In such a case, the cloud server cannot transmit a packet to the MFP as a transmission source. However, a packet can be transmitted from the MFP to the cloud server, and a response packet can be returned from the cloud server to the MFP, which is the transmission source.
By adding contents to be conveyed to the response packet, information can be transmitted from the cloud server to the MFP. More specifically, only one method for the MFP to realize receiving an image of a processing result from the cloud server is to transmit the packet (polling packet) to the cloud server and receive the response packet therefrom.
When the MFP transmits the above-described processing (referred to as a “job”) to the cloud server, a job (preceding job) from another device may already have been transmitted to a cloud server side. When a great number of jobs, a great number of pages, or a great amount of processing of the preceding jobs has been transmitted (when the cloud side is crowded), it takes time until the processing result corresponding to the job transmitted by the MFP itself is returned from the cloud server. In such a case, until the processing result is returned, the MFP continues transmitting a polling packet to the cloud server. As a result, a problem that the MFP consumes wasteful electric power arises. Further, since the MFP continues transmitting the polling packet until the processing result is returned, a load for communicating with the cloud server is increased accordingly.